1. Field of the Invention
The present invention falls within the field of dynamic management of battery recharging with electric power.
The invention relates in particular to a system of dynamic and forward management of battery recharging with electric power, in particular the method for implementing same.
Such a system will find a particular application in the management of battery recharging for a fleet of vehicles, especially vehicles provided with electric or hybrid powertrain.
It should be noted that these vehicles can consist, preferably, but not exclusively, of land vehicles, such as cars, motorcycles or scooters, but also eventually of marine or water vehicles such as boats, even aerial vehicles such as aircrafts.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
At present, the users of the electric vehicles carry out the recharging of their battery by connecting to a single point of power supply located on a site. This recharging takes place for a period during which each vehicle is parked, immobilized for the time required for fully or partially recharging the batteries, so as to achieve maximum battery life. This recharging period can take place during the night, at the user's home, or during daytime at his workplace.
Many problems arise because of the number of vehicles to be recharged relative to the point of power supply of said site. It is difficult to adapt this power to a number of vehicles likely to vary, to decrease, but most certainly to increase over time in the medium to long term. For these reasons of additional costs of installation and operation, it is difficult to contemplate an oversized power capacity of the point of supply in anticipation of the future, while less power could be enough.
Therefore, a recharging point is likely to become overloaded or to trip because the recharging of the vehicles occurs simultaneously over one and the same period, i.e. mainly off-peak periods. Conversely, because of the recharging times needed, it is not possible to contemplate recharging successively all vehicles over too short a period of immobilization.
It is therefore necessary to manage a schedule for recharging the batteries of a fleet of electric vehicles.
To this end, it has already been devised, through EP 2219278, to check the status of charge of each battery and to derive from same a sequence for recharging vehicles depending on the status of charge and the power available at the point of supply. In addition, this solution estimates a potential future consumption based on the current status of charge of each battery. In brief, a minimum level of charge to be achieved is calculated based on the discharge of the battery being observed. The beginning of the next use, corresponding to the start of the vehicle and to the end of recharging, also enters into consideration. Based on all these parameters, a schedule of simultaneous and successive recharging of all the vehicles is automatically calculated.
Although this solution allows to schedule the recharging of several cars, it is however not satisfactory because of the estimated aspect of the level of charge to be reached. A user may indeed use his vehicle during the week to go to his workplace, leading to a regular daily consumption, but not use it during the weekend, on Saturdays and Sundays. It will then only be necessary to contemplate its recharging before Monday morning. Conversely, a user may need his car during the weekend for larger trips, while he uses it less on weekdays. Infinite possibilities can be contemplated, which do not permit to have a minimum level of charge adapted to the next trip of the vehicle, or to best optimize the recharging and the amount of electricity being consumed.
Moreover, such a solution must necessarily communicate with the electrical management system of the vehicle, in order to retrieve information. Because of the disparities existing between two manufacturers, as well as the powers of each battery for a given vehicle, said solution must integrate communication means that provide such compatibility, which makes its design and implementation more complex. Therefore, in reality, this solution permits to manage the recharging schedule only for vehicles of the same manufacturer.
An alternative solution is described in U.S. 2011/193522, relating to a system for managing the affluence and access by a user to a network of recharging stations, each station was equipped with one or more terminals, i.e. several power-supplying points in the meaning of the present invention. The aim is here to remotely inform a user about the availability of a recharging terminal, then to permit him to book a time slot with an available terminal, the same terminal or a terminal located nearby in the same geographical area.
To this end, such a system indicates, at a user's request, the recharging schedule of one or more stations, while indicating the shortest time remaining before one of said stations becomes free and is vacant, permitting the user to then contemplate recharging his vehicle at that time. The user must then book a time slot for recharging, while indicating or not the recharging time he wishes. Once it has been booked, the user must go to the site for recharging.
It should be noted that this document provides for identifying the vehicle, in order to know whether it has already been recharged before, using the previous recharging time recorded at a server that remotely manages all the sites.
It is therefore a mere management of an agenda, which indicates when and for how long a station is free for a limited period, namely based on a duration of recharging already performed by a user identified in the system. In other words, said system uses the previous recharging time of a user as a basis for the duration of the minimum time slot he wishes to book, which said system compares with the time slots of availability of the terminals.
Such a system does in no way take into consideration the previous recharging times, but only the previous duration, in order to define and find an at least equal time slot to permit recharging the vehicle, said time slot corresponding to said recharging duration previously recorded at the level of said server.
More specifically, in this system, the assignment occurs by stacking, similar to a stack of the FIFO type, for “First In First Out”. In other words, for a given station, a user must wait until the end of the previous recharging operations in order to be able to book the next available slot to perform its own recharging.
This solution does not at all take into consideration the calculation of the optimal time for recharging several vehicles based on the behavior of each user. Such an agenda management does not take into consideration a user who arrives earlier and should theoretically leave later, compared to another user who arrives later, but should theoretically leave earlier. The aim is only to make the recharging times follow each other in an agenda, without any possibility of making them overlap, nor explicitly taking into consideration the electrical power of the terminals. In addition, there exists no optimization of the system to come as close as possible to the nominal power limit of each power-supply point.